1. Field of Invention
The present invention relates to a projector. More specifically, it relates to a projector for modulating and, subsequently, for enlarging and projecting a light beam irradiated from a light source to form a projection image.
2. Description of Related Art
Recently, a projector has come to be used in various circumstances such as technical review meeting at research and development department etc. by enlarging and projecting a data of CAD/CAM/CAE (computer-aided design/computer-aided manufacturing/computer-aided engineering), various seminars and training institutes and classroom lessons in audiovisual education, as well as company meeting and presentation on business trip. Further, the projector has come to be used for projecting medical images and data such as CT scanning (computed tomography scanning) and MRI (magnetic resonance imaging) to serve for studying remedies and medical guidance and for effectively staging exhibitions and events attracting a lot of people.
Since projectors are now used in such various environments, various performance and functions are required for projectors, which include light-weight compact model for improving portability, high-intensity model and high-definition model for improving quality of images and high-function model capable of being connected to various digital machines and mobile tools.
The projectors are expected to be used in wider areas, so that projectors with more values added are now intensely developed targeting new area for use.
The aforesaid projectors accommodate a plurality of optical components thereinside, and modulate, enlarge and project a light beam irradiated from a light source using the optical components to form a projection image.
Such optical components includes a polarization converter for converting the light beam irradiated from a light source via a beam splitter such as a lens array into a predetermined linear polarization beam for improving light utilization efficiency and for eliminating various optical aberrations, and a lens array for transmitting a plurality of partial beam irradiated from the polarization converter to a light modulator such as liquid crystal panel and to superpose the light beam on a display area of the light modulator.
Such polarization converter and lens array are respectively fixed on a inner case supporting the elements at a predetermined position adjacent to the light source. In fixing the elements, the position of the polarization converter and lens array relative to optical axis of the light incident on these elements is adjusted.
However, since the polarization converter and the lens array have to be independently fixed to a dedicated fixing portion while adjusting position thereof relative to optical axis, optical axis adjustment is troublesome. Further, a lot of work is necessary for fixing the components, thus requiring a lot of time for assembling the projector.
Further, since two fixing portions for the polarization converter and lens array have to be provided on the inner case constituting the projector, the structure of the inner case becomes complicated. Especially, since the polarization converter and the lens array have to be very closely disposed, the fixing portion has to be provided closer, so that the structure of the inner case becomes further complicated.